Based on the cluster model with phenomenologicalα-core potential,αdecay half-life of europium isotopes are investigated.The calculated results indicate that cluster model is more appropriate for europium isotopes than the Coulomb and Proximity Potential Model.In order to study the isospin effect of nuclear potential,we introduce the factor f,which is used to modify phenomenologicalα-core nuclear potential.Using the existing experimental data ofαdecay half-life,the values of factor ffor europium isotopes are calculated.The results indicate t...